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kubespray/docs/etcd.md

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+# etcd
+
+## Deployment Types
+
+It is possible to deploy etcd with three methods. To change the default deployment method (host), use the `etcd_deployment_type` variable. Possible values are `host`, `kubeadm`, and `docker`.
+
+### Host
+
+Host deployment is the default method. Using this method will result in etcd installed as a systemd service.
+
+### Docker
+
+Installs docker in etcd group members and runs etcd on docker containers. Only usable when `container_manager` is set to `docker`.
+
+### Kubeadm
+
+This deployment method is experimental and is only available for new deployments. This deploys etcd as a static pod in master hosts.
+
+## Metrics
+
+To expose metrics on a separate HTTP port, define it in the inventory with:
+
+```yaml
+etcd_metrics_port: 2381
+```
+
+To create a service `etcd-metrics` and associated endpoints in the `kube-system` namespace,
+define it's labels in the inventory with:
+
+```yaml
+etcd_metrics_service_labels:
+  k8s-app: etcd
+  app.kubernetes.io/managed-by: Kubespray
+  app: kube-prometheus-stack-kube-etcd
+  release: prometheus-stack
+```
+
+The last two labels in the above example allows to scrape the metrics from the
+[kube-prometheus-stack](https://github.com/prometheus-community/helm-charts/tree/main/charts/kube-prometheus-stack)
+chart with the following Helm `values.yaml` :
+
+```yaml
+kubeEtcd:
+  service:
+    enabled: false
+```